Here is a pick of what I did for the cutoff switch. It is not high tech, but east to get to, bullet proof, and cost $30 total and solved how I was going to extend the wires to get back to the battery box.
2009 King of the Hammers
BUCK Wild Racing
Co-driver: Pat Quirk
Rover Tracks www.rovertracks.com
DJ Safety www.djsafety.com
West Coast Rovers www.westcoastrovers.com
Reel Driveline www.reeldriveline.com
Made it further than half of the other guys, but the Hammers won.